Automatic stoker



Nov. 19, 1929. w. J. WOODCOCK 1,736,565

AUTOMATIC STOKER Filed Jan. 31, 1927 INVENTOR Willard J Waodcock B mmuh ATTORNEY S Patented Nov. 19, 1929 UNITED STATES PATENT OFFICE AUTOMATIC STOKER Application filed January 31, 1927. Serial No. 164,698.

This invention relates to improvements in stoking mechanism for furnaces and is particularly applicable to under-feed stokers of the type shown for example in my United States patent application Serial No. 146,582, filed Nov. 6, 1926.

It is a primary object of the invention to prevent the fuel from packing adjacent the point where it is introduced into the combustion chamber.

It is another object to accomplish this result by means of arelatively simple mechanism which will not materially increase the cost of the installation but which will at all times efiiciently prevent the packing of the fuel in the fuel passageway and which will accordingly prevent the apparatus from being stalled through inability to displace the partially introduced fuel.

These and other objects will appear more fully from the following description when considered in connection with the drawings in which:

Fig. 1 is a vertical sectional view of a typical under-feed stoker showing my invention applied thereto.

Fig. 2 is an enlarged perspective view of the fuel feeding ram provlded with my invention.

In under-feed stoker mechanism wherein a plunger or ram advances the fuel from an outside hopper into the fuel retort in the combustion chamber there has been experienced considerable difiiculty with certain kinds of coal and particularly where the coal is damp,

in that the coal tends to pack in the fuel inlet adjacent the most advanced points reached by the fuel ram. This difliculty has been entirely overcome by the present invention and in addition the power required for operating the stoker has been materially reduced. This will be readily understod from the following detailed description of the invention.

Referring to the details of the drawings there are disclosed certain parts of a typical furnace with the boiler 4, combustion chamber 5, bridge wall 6 and furnace wall 7 of a usual t pe as will be readily understood by those s illed in this art.

Fuel is fed into the lower portion of the combustion chamber 5 by being advanced in the fuel retort 8 through the operation of a power cylinder 9 and piston 10 it being understood that power is to be applied to either side of the piston for advancing or retracting the fuel feeding ram 12 in the ram casing 13. In the present instance the power piston 10 is shown as connected to the ram 12 by means of the connecting rod 11 which pass through an inner wall 15 of cylinder 9 the rod being screw threadedly engaged within the inner sleeve 17 within the ram 12. The ram casing 13 supports the fuel hopper 14, the ram 12 reciproacting in the casing 13 across the opening in the lower portion of the hopper 14 for advancing fuel from the hopper into the fuel passage 16. From the passage 16 the fuel is carried inwardly into the retort 8 by means of the pusher rod or rods 18 formed with any desirable number ofsuitablyshapedprojecting elements 20, the pusher rod 18 being connected in the present instance to the ram 12 and. power mechanism 10 by means of the ram projection 21 secured to the extension 19 of the pusher rod 18.

In order to prevent the fuel from packing in the fuel passage 16 I have provided a stirrer 22 formed with a projecting portion or cross head 23 and having an integral shank 24 which may be screw-threadedly engaged within the inner sleeve 17 of the ram 12 or otherwise suitably secured to the ram for movement therewith. The cross head 23 as indicated herein is relatively small compared with the cross-sectional area of the fuel passage 16 so that it may be double acting for both the forward and rearward movements thereof. It will serve only to agitate the fuel and prevent packing of the same in the fuel passage 16. The cross head 23 of the stirrer 22 preferably operates between the foremost point of movement of the ram 12 and the rearmost point reached by the rear,or outer projecting member 20 of the fuel advancing mechanism since this is the place the fuel has the greatest tendency to pack.

The operation of the mechanism will be readily understood from the above description. \Vhen power is supplied to the power mechanism 9-10 the ram 12 will be intermittently reciprocated beneath the hopper 14 each movement of the ram advancing a certain amount of fuel into the passage 16 thus forcing a certain amount of fuel already in the passageway further into the combustion chamber 5 and retort 8. The pusher rod 18 and projecting members 20 serve to advance the fuel in the retort 8 and to prevent caking or packing of the fuel in the combustion chamber 5 in advance of the passa e 16. The reciprocation of the stirrer 22 bac ward and forward in the fuel passage 16 maintains the fuel in this passageway in a loosened condition such that the ram 12 is never stalled and unable to advance the fuel into and through the passage 16 and at the same time the power required for reciprocating the plunger 12 is materially reduced.

It will be readily understood that the particular mechanism herein shown merely represents one adaptation of my invention and that changes may be made therein as long as they fall within the scope of the appended claim.

I claim:

In a fuel stoker provided with a restricted fuel passage and a retort, a hopper, a reciprocating ram for advancing fuel from said hopper into said fuel passage, a reciprocating pusher formed with a projecting element for advancing fuel in said retort, and a double acting stirrer positioned between said ram and projecting element and movable in said fuel passage or agitating the fuel therein, and means for operating said ram, projecting element and stirrer, said ram, stirrer and projecting element having substantially successive paths of movement, outwardly of said passage, in said passage and inwardly of said passage respectively.

Signed at New York, in the county of New York, and State of New York this 28th day of January A. D. 1927.

WILLARD JAY WOODCOCK. 

